There is something deeply instructive about the present tut-tutting over how the authorities in Moscow are restricting the access British detectives are allowed to key witnesses in the Litvinenko affair. The lessons have nothing to do with whether the Russia of Vladimir Putin is becoming a dark, increasingly autocratic place that is dangerous for critics of the state. It is. Nor do they instruct us on whether any of those suspected of having a hand in his murder should stand trial wherever they are found. They should. Finally, there can be little dispute over whether we should press for the extradition of anyone involved. We most certainly should.

What is subtly revealing is the way in which our disapproval of the actions of Putin's government has exposed a peculiar trait in our national identity - a British 'exceptionalism' which posits that while it would be unthinkable for Russian detectives (or those of any other nation) to pursue an investigation on British soil, our police should be allowed to act as if the entire world is within their jurisdiction.

The Litvinenko case is hardly singular as an example of the British sense of the superiority of our values, a moral code we believe the world should bend to. It is an attitude shared in large part by many of our politicians, media figures and even public intellectuals. Its hallmark is a curiously uncritical set of double standards typically expressed in an affronted tone of self righteousness.

So we complain about Russia becoming ever more of a police state while, as Henry Porter has pointed out on numerous occasions in these pages, our government has been enacting legislation that is turning this country into a 'surveillance' state. We complain about the actions of suspected Russian spies on our soil, conveniently forgetting that several of MI6's officers were caught in an act of egregious espionage in Moscow laughably involving a 'fake rock'. Further abroad, we criticise China's record on democracy since it came to power in Hong Kong, conveniently forgetting that while we were 'masters' there, we did little to promote democratic values. And China's recent investments across Africa, including, it must be said, in some of the most unsavoury regimes on the planet, have prompted a wave of indignation among commentators in Britain, who have conveniently forgotten that the dire state of Africa is the result at least in part of our colonial and post-colonial policies. We ignore the possibility, too, that Chinese investment policies might succeed - where ours have so palpably failed - in lifting the continent out of its economic misery.

Our record at home is not much to shout about either, despite our willingness to lecture the rest of the world on its problems, as we did a year ago amid France's outbreak of suburban rioting. This is a country where casual Islamophobia finds expression across the political divide, to a degree that even liberal intellectuals are unembarrassed to make remarks that you could not imagine being made about Jews or other races without a reaction of absolute horror.

After years in which this country seemed to be readjusting to a more realistic sense of its place in the world, more recently there has been a resurgence across the political spectrum of a culturally conservative and ultimately hubristic belief in Britain's special role for good in the world. Indeed, it was this misplaced, at times almost evangelical conviction, that in large part led Tony Blair to pursue the invasion of Iraq, calculating quite wrongly that an act that he had been warned might be illegal would be justified by its anticipated benefits.

Resurgence of the British sense of the uniqueness of its values is a worrying reversion to the postwar years. It is a lazy and complacent world view that mistakes the historical anachronism of membership of the permanent five members of the Security Council, its costly and irrelevant membership of the official nuclear club and its cadet status in the Special Relationship for a more widely significant role in the world.

And curiously, given the essentially conservative nature of the narrative, the resurgence of the British sense of uniqueness has been driven in a large part by the characters of Tony Blair and his heir apparent, Gordon Brown, who have reaffirmed the primacy of the Special Relationship with the US as a way of maintaining the UK's position at the centre of international affairs.

They have also insisted on articulating a moral leadership on international issues as diverse as global warming, the fight against poverty and the search for peace in the Middle East, views too often undermined by the subtle hypocrisy of Britain's actions.

What 'British values' are supposed to be were laid out in a speech by Tony Blair in 2000. He described them as 'qualities of creativity built on tolerance, openness and adaptability, work and self-improvement, strong communities and families and fair play, rights and responsibilities and an outward-looking approach to the world that all flow from our unique island geography and history'. In May this year, there was a suggestion that, following the London bombings, the government was reviewing whether 'core British values' should become a compulsory part of the curriculum for 11- to 16-year-olds in England.

The insistence on the uniqueness of British values is nothing new. Nor is the counter-argument that they are an overblown fiction based on an inflated post-colonial sense of our worth in the world. Historians and writers such as Correlli Barnett in The Audit of War and, more recently, Robert Winder in Bloody Foreigners have effectively deconstructed many of the national myths on which our exclusive sense of worth is founded.

What is worrying, however, is that once again we are being seduced by gazing into a distorted mirror of ourselves and liking too much what we see. It is the narcissism of national obsession. And it blinds us to the reality of how we can really effect a difference in the world.